I will skip it for the moment. Two similar crashes are suspicious. I am bothered that Boeing deployed functionality that was not documented and thus no one was trained, warned, etc. very damning oversight.
Its always good policy to wait a bit on the jumping to conclusions part of the argument. But investigations are always careful and long. The airlines who are grounding these planes are correct in my opinion as a safety engineer. The coincidence is always something that a problem investigation team has to explain and flying planes while they are studying does not make good sense.